Injection valve



June 15 1926. v 1,589,239

P. L. SCOTT I INJECTION VALVE Original Filed Feb. 2. 1920 2 Sheet s 1 E C 7/" fl V l l Inventor y MW miwl I gfmplscott .Aittorneys June 15 1926. 1,589,239

P. L. SCOTT INJECTION VALVE vOriginal Filed Feb. 2. 1920 2 Sheets-Sheet 2 hventor v 1 72270 Z. 500m;-

Patented June 15, 1926.

UNITED STATES PATENT bFl-"ICE.

PHILIP LANE SCOTT OF CHICAGO, ILLINOIS, ASSIGNOR TO STUJIEQR-DIESEL TRACTOR, CORPORATION, OF LA FORTE, INDIANA, A CORPORATION NEW YORK.

INJECTION VALVE.

, Application fled February 2, 1920, Serial No. 355,878. Renewed January 6, 1926.

My invention relates to an injection valve for internal combustion engines and the like and has particular reference to the perforated plate through which the liquid is sprayed or injected. N

The injection valve comprises in general terms, a housing supplied with liquid under pressure,a removable perforated spray plate forming one of the walls of said housing, the

W plate being rigidly held about its periphcry or edge. There is an adjustable needle valve adapted normally to close the perforation in the plate and to be forced against the plate so as to deflect it setting up an initial strain in the plate which will permrit further deflection of the plate only. after the pressure on the liquid in the housing has.

exceeded a certain predetermined point when the plate will be deflected and the liquid will be forced out under high pressure and high velocity through the aperture between its edges and the needle valve to be injected as a spray into the engine or the receptacle into which the injection takes place.

It is well known that in a perforated or apertured plate rigidly held about its periphery, the weak point is the surface of the perforation and the metal immediately surrounding it. When the plate, at this orifice or perforation is subjected both to erosion by the high pressure of the stream of liquid, and to distortion and bending caused by the pressure of the liquid, this erosion and this bending or distortion is concentrated at the perforation and the life of the disc or plate and of the orifice therethrough is greatly reduced because of the combined action of these two destructive forces tend- 0 ing to change the size and shape of the orifice and thus destroy the fit of it between it and the needle. This is disadvantageous because it results in uncontrolled changes in the spray orifice and thus makes it impossible to obtain satisfactory constant condi-, tions of operation when the injection valve is used as it is intended in my preferred form to use it, as an injection or spray valve for an internal combustion engine.

In order to protect the spray plate and give it the longest possible life, I propose first to re-enforce the actual walls of the perforation therethrough with a peculiarly hard substance which isembedded in the plate itself. The material may take the form of quartz, carborundum, glass, diamond, sapphire, or any other hard heat resisting substance embedded in a plate of steel or any suitable elastic metal. One solution of this part of the problem might take the form of embedding in a disc or plate of special spring steel or spring metal, a small washer of especially hard tool steel or similar material which can be as hard and as brittle as desired because being embedded in and protected by and carried by the flexible spring washer, it needs only to resist the abrasion of the liquid as it rushes out under high velocity and pressure. I protect the perforated or apertured part of the disc against distortion by leavin the perforated center of the disc thic' and thinning it off between the center and the periphery so that the bend-, ing of the disc will take place at a point removed from the perforation therethrough and the body of the disc around the perforation may thus move toward and from the needle point in a direction perpendicular to the axis thereof and thus the aperture will be provided with sharp edges and subject only to the abrasion or erosion of the liquid as it rushes out.

Experience has shown that frequently it is desirable to provide special means for controlling the shape and direction of the rate of liquid as it rushes out and a very happy Way of doing this is by weakening the walls of the orifice or perhaps it would be better to say, is by making the walls of the orifice of different strength at different points. Another way in which this can be accomplished is by changing or varying the width of the valve seat at different points and" this may or may not be accomplished by changing the thickness of the wall of the orifice or changing the strength of the wall of the orifice. In other words, the needle wears its seat on the material surrounding the orifice and ifyou so position or so treat the material as to get different thickness of walls or different strengthof walls, We find that the needle will tend to make a relatively wide seat at the high spot or the thick spot or the strong spot and a relatively narrow seat at the thin or the weak or he low spot, thus tending to permit the spray to form only at the place or places where the valve seat is narrow.

My invention is illustrated more or less diagrammatically in the accompanying drawings wherein:

Figure 1 is a vertical section of the preferred form of my valve;

Figure 2 is an enlarged section through the disc;

Figure 3 is a plan view of the disc;

Figure 4 is a section through a modified form;

Figure 5 is a plan view of the modified form;

Figure 6 is a plan view of a modified form of valve disc;

Figure 7 is a section along the line 77 of Figure 6;

Figure 8 is a plan view of a further modified form;

Figure 9 is a section along the line 9-9 of Figure 8.

Like parts are indicated by like characters in all the figures.

A is the body of an injection valve having the central bore A enlarged at its upper end. A is a packing in said enlargement. A is a supporting member screw-threaded into the enlargement of the bore A The valve body is screw-threaded into an engine cylinder wall F which is of course, only diagrammatically shown.

B is an inlet connection having the central bore B in register with the bore A of the valve and communicating through it with the central bore A.

C is a valve disc having a perforation C It is held to the valve body by the retaining cap C and is spaced from it by the gasket ring C".

l) is a valve stem in the central bore A, reduced throughout the greater part of its length as at D and terminating in an enlarged valve head or point D, which engages the disc C, and normally closes the perforation C.

In the form shown in Figures 4 and 5. I show the valve disc C having a central thickened boss E surrounding the aperture. This thickened boss has two purposes. It re-enforces the disc immediately surrounding the perforations so that it cannot bend, but bends at the thinner peripheral portion as it is forced away from the needle valve by the pressure of the liquid in the valve, thus the sharp edgesof the perforation move towardand from the needle valve'as above suggested but always in a plane perpendicularto the 'liIlG'JOf movement and the axis of the valve. More than: this however, because this boss :h as, a relatively .smallijsuperficial area, it is possible to stone off its surface so as to give a sharp edge to the perforation and this would not be possible, commercially at least, if it were necessary to stone off the entire surface of the disc.

The reason for the importance of this reenforcement around the aperture is that if the disc Were of uniform cross section instead of bending upon a gradual curve throughout the periphery, experience shows that the deflection would be concentrated right about the aperture and not spread throughout the entire extent of the disc.

In the preferred form shown in Figures 2 and 3 I have shown a resistent carborundum, glass or diamond plug in which the sharp walled aperture is made. The outer wall of this plug F is tapered as at F so that it may be forced into and make a snug fit with the tapered seat in the spray disc and so that the middle of the spray disc may be bent or forced over so as to hold the hard plug in position and make a gas and fluid tight joint between it and the needle. Obviously this rigid or brittle plug must be protected against distortion and it should be used with such a device as that shown in Figures 4 and' 5 wherein the deflection of the disc is concentrated at a point removed from the perforation therein.

In the'modified form shown in Figures 6 and 7 I provide the spring disc with a boss on one side, preferably on the side removed from the combustion chamber. The aperture is made through the boss as in the other forms and then the two opposite sides of the boss are cut away as at X, X so that the boss becomes angular in cross section as shown in Figure 7 with a fiat upper surface X parallel with the plane of the disc. This shaping of the boss makes it possible to control the shape and direction of the spray.

The reason for this difference in thickness of the seat is, of course, that where the wall is thin or unsupported or relatively flexible, as it is away from the thicker or heavier part of the boss, there is not so much resistance to the pressure of the needle and the entire body of material tends to deflect away from the needle and thus is not so readily permanently deformed, and therefore, the seat is not so deep or wide.

By my arrangement, I provide a single unit structure which as the fuel is injected, atomizes or sprays it, and at the same time, forms the jet of sprayed or atomized liquid, and directs that jet into the combustion chamber in some predetermined direction, thus making it possible to intelligently design the engine and its parts so that there w1ll be a minimum of waste air or air and fuel uncommingled in the combustion chamber. Obviously, while I prefer to do this as I have suggested by a single valve and valve seat. where the spray, the shaping of the jet, and its direction are accomplished at the same time and same place, and by the same means, it is nevertheless quite conceivable that under many conditions of design and operation, it might be desirable to use other devices for accomplishing different parts of the result at different times or places and clearly then, it would not be a departure from the spirit of my invention to change some of the conditions set out above as for instance. atomizing and controlling or directing the jet at different points or by different mechanisms.

What I claim is 1. An injection valve comprising a hollow valve body, an apertured valve disc secured to one end of it, a valve rod located within said valve body adjustably secured at one end to it and carrying a needle point at the other, said needle point positioned with in and normally closing the aperture in said valve disc, said valve disc adapted to move outward from said needle point responsive to the pressure of liquid against it, the disc being reenforced about the aperture.

2. In an injection valve, the combination of a movable valve disc, having a perforation therein, and a needle point adapted to penetrate therein and normally to close said perforation, the disc being re-enforced about the perforation.

3. An injection valve-comprising a hollow valve body, an apertured valve disc secured to one end of it, a valve rod located within said valve body adjustably secured at one end to it and carrying a needle point at the other, said needle point positioned within and normally closing the aperture in said valve disc, said valve disc adapted to move outward from said needle point responsive to the pressure of liquid against it, the disc being thickened about the aperture and being provided with a relatively thin annular portion surrounding such thickened portion.

4. In an injection valve, the combination of a valve disc, having a perforation therein and a needle point adapted to penetrate therein and normally to close said perforation, the disc being thickened about the perforation and being provided with a relatively thin annular portion surrounding such thickened portion.

5. An injection valve comprising a hollow valve body, an apertured valve disc secured to one end of it, a valve rod located within said valve body adjustably secured at one end to it and carrying a needle point at the other, said needle point positioned within and normally closing the aperture in said valve disc, said valve disc adapted to move outward from said needle. point responsive to the pressure of liquid against it, the disc being thickened about the aperture and being provided with a relatively thin annular portion surrounding such thickened portion,

an insert of relatively hard material carried by said valve disc, the aperture being lo cated within such insert.

6. In an injection valve, the combination of a valve disc, a perforation therein and a needle point adapted to penetrate therein and normally to close said perforation, the disc being thickened about the perforation and being provided with a relatively thin annular portion surrounding such thickened portion, an insert of relatively hard material carried by said valve disc, the perforation being located within such insert;

7. A spray disc for injection valves having a central thickened boss, a relatively thin flexible flange extending outwardly from said boss and surrounding it, said disc adapted to move to open in response to the pressure of liquid against it, the surface of the boss being substantially-parallel with the flange, and a spray aperture through the boss.

8. The process of manufacturing spray discs which consists in cutting a blank from a rod, machining off the blank about its periphery so as to provide a relatively thin flange surroundinga thickened central boss making a hole through the boss and then stoning off the surface of the boss to sharpen the edges of the hole.

9. An injection valve including a spray disc having a central spray aperture therethrough, means for holding the periphery of the disc rigidly in place, the disc adapted to be deflected under hydraulic pressure to open the spray orifice, the disc being free to bend only at points removed from the spray aperture.

10. An injection valve comprising a peripherally held perforated disc, a needle valve normally closing the perforations, means for supplying hydraulic pressure to deflect the disc to bring it out of engagement with the needle valve, the disc being free to deflect only near its periphery.

11. An injection valve comprising a pcripherally supported and perforated disc, a needle valve normally closing the perforation, means for supplying hydraulic pressure to deflect the disc to bring it out of engagement with the needle valve, the disc PHILIP LANE SCOTT. 

